klogs vs. mailing lists

On the klogs mailing list, John Garside asks

What advantages do klogs have over lists such as (an
ad-free) yahoogroups and the like?

This is a surprisingly difficult question, and I'm choosing to write some rambling answers here rather than on-list because they might veer off topic (this itself is part of the answer, of course: lists tend to be topic-specific, but blogs/klogs are usually person-specific). It's somewhat easier to answer than a parallel question "klogs or newsgroups?" which might be raised.

A few dimensions of difference:

• Categorisation. Making an effective taxonomy, at any point in time, is incredibly difficult. Maintaining an effective taxonomy over time is at least as hard. If you want to use mailing lists for knowledge logging, there's an implied setup cost in thinking a little about taxonomy before you begin, and there's always an "activity cost" in thinking about the correct place to write. On the other hand, blogs setup cost is per-person, not per-topic, and the categorisation is much more fluid. This reduces the "activation cost" in documenting your activities.
  
• Purpose. Much use of mailing lists is for Q&A-type interaction, in a similar way to many effective uses of Notes/Domino and Web discussion forums. This is very different from the "k-logging" purpose of simply documenting, interrelating, and raising issues of concern. K-logs also fit extremely well with Groove shared spaces: blogging for documentation, Groove for joint action.
  
• Interrelatedness. The blogging world is very fast evolving some powerful ways of linking, relating and bringing together of topics and people: RSS, blogroll lists, "trackback" (emdedded RDF referents in topics), aggregators and publishing tools. Mailing lists sometimes (depending on your mail-reader software) to a reasonable job of threading, but more often than not, even this is broken.

It's worth reiterating the fundamentals in common, too. Knowledge Management 101: "write it down". Documenting your immediate activity in a relevant place is valuable. It helps others find what you're talking about (now or later). It helps the author clarify - I've found this myself many times, that simply writing about current work is a very helpful context-switch, and forces you to continuously re-evaluate its structure and goals.